well, my DD (2001 GP GT), has had some "minor" factory audio issues 
.. the car has OnStar, steering sheel controls, is nonBOSE/Monsoon, has RAP's, and is pretty much like our GMT's, just a little bit older... my front 2 door speakers and tweeters were blown, and some buttons on the steering wheel werent working... so i was like F*** it, let me spend some of my hard earned money...
soooooo... i went and bought and installed everything yesturday, and i am more then impressed with all of it... it does exactly what i wanted it to do and then some... my GP is my DD, so i didnt want anything too crazy.. just basic stuff... no bass, no complicated harness', and didnt care if i lost steering wheel controls, RAP's, etc... But with the cheapy $15 harness, guess what... i retained all my RAP's, chimes, and my stereo stays on until i open my door, just like factory... I love this car.. i guess with the GP, the RAP's are controlled through the BCM... so unless you have BOSE, basic wire harness' are ok to use... 
Items that i bought...
Sony CDXGT56UI AM/FM/CD Detachable Faceplate, front auxiliary input, MP3/WMA/AAC playback, USB 1-wire for iPhone/iPod, Sirus XM sat radio connector ready, suppplied wireless remote..... $79.99
Rockford Fosgate R152-S Prime Coaxials 5.25" Full Range Coaxial (w/tweeters) 35W RMS/70W Peak for my 2 front doors.... $50.00
GM4001 GM Harness 701858... $9.85
993320 Pontiac Kit...$15.93
ADGM1 Antenna Adapter 40GM10... $8.95
so for my grand total plus tax, i paid $169.70 and i installed it all myself... thats a deal in my book any day... and like i said... it does what i wanted it to do... has my front mount USB so i can listen to my flash drives and i have sound at all the speakers now and it absolutely SCREAMS... it was driving me nuts having 2 blown door speakers lol... im sure everyone knows what the pieces look like taken off, but here are some pix anyway...
.. the car has OnStar, steering sheel controls, is nonBOSE/Monsoon, has RAP's, and is pretty much like our GMT's, just a little bit older... my front 2 door speakers and tweeters were blown, and some buttons on the steering wheel werent working... so i was like F*** it, let me spend some of my hard earned money... soooooo... i went and bought and installed everything yesturday, and i am more then impressed with all of it... it does exactly what i wanted it to do and then some... my GP is my DD, so i didnt want anything too crazy.. just basic stuff... no bass, no complicated harness', and didnt care if i lost steering wheel controls, RAP's, etc... But with the cheapy $15 harness, guess what... i retained all my RAP's, chimes, and my stereo stays on until i open my door, just like factory... I love this car
.. i guess with the GP, the RAP's are controlled through the BCM... so unless you have BOSE, basic wire harness' are ok to use... Items that i bought...
Sony CDXGT56UI AM/FM/CD Detachable Faceplate, front auxiliary input, MP3/WMA/AAC playback, USB 1-wire for iPhone/iPod, Sirus XM sat radio connector ready, suppplied wireless remote..... $79.99
Rockford Fosgate R152-S Prime Coaxials 5.25" Full Range Coaxial (w/tweeters) 35W RMS/70W Peak for my 2 front doors.... $50.00
GM4001 GM Harness 701858... $9.85
993320 Pontiac Kit...$15.93
ADGM1 Antenna Adapter 40GM10... $8.95
so for my grand total plus tax, i paid $169.70 and i installed it all myself... thats a deal in my book any day... and like i said... it does what i wanted it to do... has my front mount USB so i can listen to my flash drives and i have sound at all the speakers now and it absolutely SCREAMS... it was driving me nuts having 2 blown door speakers lol... im sure everyone knows what the pieces look like taken off, but here are some pix anyway...
